Edge bit structure for blade of earth working implement



0a. 13, 1964 J. WQOD 3,152,411

EDGE BIT STRUCTURE FOR BLADE 0F EARTH WORKING IMPLEMENT Filed June 16, 1961 INVENTOR. JAY .1. W000,

A T TORNEYS United States Patent Ofiice 3,152,411 EDGE BIT STRUCTURE FOR BLADE F EARTH WORKING IMPLEMENT Jay J. Wood, 111) Mariposa, Watsonville, Calif. Filed June 16, 1961, Ser. No. 117,565 3 Claims. (Cl. 37143) The present invention relates to blade-type earth working implements and pertains more particularly to a replaceable edge bit structure for the blade of such an implement.

In blade-type earth moving equipment, such as road grading scrapers and bulldozers, the cutting edge of the blade thereof is subjected to severe thrust and impact stresses and abrasion. Up to the present time it has been common practice to provide replaceable plates or bits which are bolted in place along the lower edge of the blade of such a piece of equipment. When these prior bits, each of which is a single, unitary plate, become worn down to a point requiring replacement, either the lower edge portions of these plates are built up by welding, or the entire remaining portions of the plates are removed and replaced with new ones.

It is usually cheaper and quicker to replace such bits than it is to build them up by welding. However, when the former procedure is followed, the remaining portions of the bits, which are scrapped when discarded, constitute by far the major portions of the bits and obviously represent a substantial scrap loss. Also, the removal and replacement of the entire bits entails a considerable amount of labor, and down-time for the machine, which add still more to the cost of bit replacement.

In the past, attempts have been made to provide a blade edge bit wherein only a cutting edge portion thereof was replaceable. However, such bits usually have not been capable of withstanding the tremendous stresses to which they were subjected, and have not, therefore, gone into widespread use.

The present invention provides a replaceable, two part, edge bit structure for the blade of an earth moving implement, which bit structure comprises a replaceable lower edge member mounted in secure, interfitted and interlocked engagement with a mounting member, the latter of which is permanently and strongly secured to such blade.

A further object of the invention is to provide a two part edge bit structure for the blade of an earth moving implement, wherein a support plate is secured to the blade of such implement in upwardly spaced relation to the lower edge of such blade, and an easily replaceable lower edge bit member is retained by the support plate and is backed by the exposed lower edge portion of the blade upon which the bit structure is mounted.

A further object of the invention is to provide an improved, economical, simple, rugged, easily replaceable two part bit structure for the cutting edge of the blade of an earth working implement.

These, and other objects and advantages of the invention, will be apparent from the following description and the accompanying drawings, wherein:

FIG. 1 is a perspective view of a bulldozer, the blade of which is provided with a replaceable edge bit structure embodying the present invention.

FIG. 2 is an enlarged, fragmentary front elevational view of an end portion of the blade shown in FIG. 1, edge bit structures embodying the invention being mount.- ed thereon.

FIG. 3 is an exploded view of the parts shown in FIG. 2, the bolts for interconnecting the parts being omitted.

FIG. 4 is an enlarged, fragmenary, sectional View taken along line 44 of FIG. 2.

3,152,411 Patented Get. 13, 1964 FIG. 5 is an enlarged, fragmentary, sectional view taken along line 5-5 of FIG. 2.

Briefly, in FIG. 1 an otherwise conventional bulldozer A has mounted along the lower edge of its blade 10, a plurality of aligned edge bit structures 11 and 12 embodying the present invention. These edge bit structures comprise, respectively, a pair of corner bit structures 11 and 11 and a plurality of substantially identical intermediate bit structures 12. The bit structures 11 and 12 comprise, respectively, an upper support member 11a and 12a, fixedly secured to the dozer blade 19 in slightly upwardly spaced relation to the latters lower edge 13, and replaceable lower edge bit members 11b and 12b. The latter are removably secured to the dozer blade 10 in interfitted, interlocked relation with their respective sup port members 1101 and 12a.

Referring to the drawings in greater detail, the corner bit structures 11 and 11' are similar, but opposite in structure, and the intermediate bit structures 12 are all alike. The latter occupy and fill the entire space between the two corner bit structures. All of the bit structures are of suitable strong tough material, such as steel or alloy plate of suitable thickness.

Since the corner bit structures are similar to each other except for the fact that they are relatively reversed, only the one 11 thereof will be described in detail herein. The lower edge of the corner support member He is beveled upwardly and rearwardly toward the dozer blade 11? as at 14 (FIG. 4), and has two notches 15 therein (FIGS. 2 and 3), one adjacent each end of the support member. The edges defining the upper end of the notches 15 are also sloped at 14' similarly to the lower edge 14 of their support member 11a.

Each corner support member 11a is secured to the dozer blade 16 by the through bolts 17, inserted in registering holes provided therefor in the support member 11a and the dozer blade 10. The heads of the bolts 17 are countersunk flush with the forward surface of the support member.

The lower or edge bit member 1112 is provided with a pair of integral, upwardly extending tabs 1a thereon, of a size and shape for close, interfitted insertion into the notches 15 in its mounting members 11a. The upper edge of each edge bit member 11b, and also the upper edges of the tabs 19 thereon, are beveled for close, interfitted relation with the correspondingly beveled, opposed edge portions of its mounting plate 11a.

The two part edge bit structures 11 and 12 are mounted on the forward or working side of the blade 10, and along the lower or cutting edge 13 thereof. Each lower, replaceable edge bit member 11b and 12b overlaps the portion 213 of the blade 19 between the lower edge 13 of the blade 10 and its associated support member 11a or 1201 as the case may be.

Each corner edge bit member 1112 is secured to the dozer blade 10 by two countersunk head type through bolt-s 21, which are inserted in registering holes provided therefor in the dozer blade 10 and in each tab 19 of the edge bit member 11b.

The bolts 17 firmly anchor the edge bit member 11a to the dozer blade 11) and prevent its lateral displacement. However, the beveled overlap at 14 (FIG. 14) of the support plate 11a, in combination with the support provided by the overlapping lower edge portion at 20 of the dozer blade 11 combine with the bolts to give the lower edge bit members 11b the ability to withstand the stresses and impacts to which they are constantly subjected while in use.

The structure and mounting arrangements of the intermediate bit structures 12 are generally similar to those of the corner bit structure 11 described previously herein. Each intermediate support member 12a, like the corner bit support members 11a, is mounted in the same upwardly spaced relation to the lower edge of the dozer blade 10, and has two notches 23 in its lower edge similar to the notches 15 in the corner support member 11a. Also, like the corner support members 11a, and the lower edge of each intermediate support member 12a, the upper ends of the notches 23 therein, are beveled upwardly and rearwardly toward the dozer blade 10 as described previously herein for the member 11a. Each intermediate support member 12a is secured to the dozer blade 10 by three countersunk head through bolts 24, similar to the bolt 17 of FIG. 4.

Each intermediate lower edge member 12b, like the corner lower edge members 1112, has a pair of upwardly extending integral tabs 25 thereon for fitted insertion into the notches 23 of their respective support members 12, and the upper edges of each intermediate lower edge member 12b, and of the tabs 25 thereon, are beveled for close interfitted relation with the correspondingly beveled, opposed edge portions of their respective mounting members.

Each intermediate lower edge member 12b, like the corner lower edge member 11b, is securely attached to the dozer blade 10 by two through bolts 28, one through each of its tabs 25.

In practicing the present invention, the support members 11a and 12:: are attached in aligned relation parallel to, and spaced upwardly slightly from, the lower edge of the blade 10 of a machine upon which they are to be mounted, as shown in FIGS. 1 and 2, and are secured thereto by the through bolts 17 and 24. With the mounting members 11a and 12a thus secured to the blade 10, the lower edge bit members 1111 and 12b are then mounted on the blade 10 in closely interfitted relation with their respective mounting members 11a and 11b as best shown in FIGS. 2, 4 and and are secured in such position by the through bolts 21 and 28 as described previously herein.

In use, the lower edge bit members 111) and 12b extend below the dozer blade and provide a strong cutting edge 29. Due to their bevel-interlocked relation with their respective support members 11a and 12a, which are securely bolted to the dozer blade 10, and the support provided by the overlapping relation at between the edge bit members 11b and 12b and the lower edge portion of the dozer blade 10, an edge bit structure is provided which is simple, tremendously strong, and which provides for easy replacement of the edge bit members 11b and 12b when they become worn down to a point where replacement becomes desirable, which ordinarily will be just prior to the point at which the lower edge 13 of the dozer blade 10 would be damaged it they were permitted to wear further.

When the time comes for their replacement, these edge bit members 1111 and 12b will be worn away to the point where very little of them remains, so that when they are removed and replaced by new, similar ones, the scrap loss caused by discarding them will be negligible. Also, since only a relatively small portion of the bolts which secure the edge bit structure to the dozer blade, i.e., those in the tabs, need to be removed when replacing the edge bit members 1117 and 12b, the replacement procedure is simple, fast, and relatively inexpensive.

The invention provides a strong, simple, easily mounted edge structure for the blade of an earth working implement, and one in which the actual cutting edge members, which are subjected to tremendous impact and thrust stresses of an earth cutting operation, are so secured to the blade upon which they are mounted, and are so interfitted and interlocked with their respective support members that they are able to easily withstand these stresses.

While I have illustrated and described a preferred embodiment of the present invention, it will be understood, however, that various changes and modifications may be made in the details thereof without departing from the scope of the invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire to protect by Letters Patent is defined in the following claims:

1. In combination with the cutting edge portion of the blade of a scraper type earth moving implement, a two part edge bit structure comprising a support member of metal plate having a plurality of notches in the lower edge thereof, means securing the support member to the work engaging side of a blade of such implement in spaced relation to the cutting edge of such blade, an edge bit member of metal plate of equal thickness to the support member and having a plurality of tabs thereon shaped and positioned for closely interfitted insertion, one in each of the notches of the support member, said edge bit member being mounted in closely interfitted abutting relation with the support member, and in overlapping relation with the work engaging side of such implement blade between the cutting edge thereof and the support member, and means releasably securing the tabs of the edge bit member to the implement blade in such closely interfitted, abutting relation with the support member, the edge bit member being of a width to extend beyond the cutting edge of such blade when so mounted thereon.

2. In combination with the cutting edge portion of the blade of a scraper type earth moving implement, a two part edge bit structure comprising a plurality of support members of metal plate, each having an undercut lower edge and having a plurality of notches in the lower edge thereof, means securing the support members in aligned, laterally abutting relation along the work engaging side of a blade of such implement and in spaced relation to the cutting edge of such blade, a plurality of edge bit member of metal plate of equal thickness to the support members, and one of the same length as each support member, a plurality of tabs on each edge bit member shaped and positioned for closely interfitted insertion, one in each of the notches of the support member, the upper edge or" each edge bit member being shaped for interfitted relation beneath the undercut lower edge of its associated support member, each edge bit member being mounted in closely interfitted, abutting relation with an associated support member, and in overlapping relation with the portion of the work engaging side of such implement blade between the cutting edge thereof and the support member, a bolt through each tab of each edge bit member and through the implement blade therebeneath for releasably securing the edge bit members to the blade, each edge bit member being of a width to extend beyond the cutting edge of such blade when so mounted thereon.

3. An arrangement according to claim 2 wherein the lower edge of each support member, and the edge at the inner end of each notch therein, is beveled upwardly and inwardly toward an implement blade when the support members are mounted thereon, and the upper edge of each edge bit member and of each tab thereon is beveled for close, abutting, interfitted relation therewith.

References Cited in the file of this patent UNITED STATES PATENTS 556,529 Bulow Mar. 17, 1896 1,757,328 Mullally May 6, 1930 1,937,243 Pearch Nov. 28, 1933 2,031,548 Romine Feb. 18, 1936 2,166,800 Craig July 18, 1938 2,674,052 Newkirk Apr. 6, 1954 2,732,639 Lillengreen Jan. 31, 1956 3,029,534 Rakisits Apr. 17, 1962 FOREIGN PATENTS 88,474 Norway Dec. 10, 1956 

1. IN COMBINATION WITH THE CUTTING EDGE PORTION OF THE BLADE OF A SCRAPER TYPE EARTH MOVING IMPLEMENT, A TWO PART EDGE BIT STRUCTURE COMPRISING A SUPPORT MEMBER OF METAL PLATE HAVING A PLURALITY OF NOTCHES IN THE LOWER EDGE THEREOF, MEANS SECURING THE SUPPORT MEMBER TO THE WORK ENGAGING SIDE OF A BLADE OF SUCH IMPLEMENT IN SPACED RELATION TO THE CUTTING EDGE OF SUCH BLADE, AN EDGE BIT MEMBER OF METAL PLATE OF EQUAL THICKNESS TO THE SUPPORT MEMBER AND HAVING A PLURALITY OF TABS THEREON SHAPED AND POSITIONED FOR CLOSELY INTERFITTED INSERTION, ONE IN EACH OF THE NOTCHES OF THE SUPPORT MEMBER, SAID EDGE BIT MEMBER BEING MOUNTED IN CLOSELY INTERFITTED ABUTTING RELATION WITH THE SUPPORT MEMBER, AND IN OVERLAPPING RELATION WITH THE WORK ENGAGING SIDE OF SUCH IMPLEMENT BLADE BETWEEN THE CUTTING EDGE THEREOF AND THE SUPPORT MEMBER, AND MEANS RELEASABLY SECURING THE TABS OF THE EDGE BIT MEMBER TO THE IMPLEMENT BLADE IN SUCH CLOSELY INTERFITTED, ABUTTING RELATION WITH THE SUPPORT MEMBER, THE EDGE BIT MEMBER BEING OF A WIDTH TO EXTEND BEYOND THE CUTTING EDGE OF SUCH BLADE WHEN SO MOUNTED THEREON. 